Only just got home. VR6 misfire

[Jim Bowen 1]

I went for this one

 

https://www.battery2u.co.uk/type-063-varta-car-batteries-c6-silver.aspx

[vw rule 19]

Yeah that's got 520 CCA so that should be fine Jim.

 

Si

[robrado974 1]

Interesting about the battery. Mine is a 550 cca . I hope you get the miss fire sorted Jim . Once I’ve sorted my thermostat housing out , I will be trying to source my poor idle problems. I tried the Maf, but the engine started to stutter, so it’s not that.

[Jim Bowen 1]

It does seem never ending Rob, no matter how much you spend/replace there's always another issue just around the bend.

 

Got the alternator to an electrical place, the guy said when he took the plastic cover off it was very rusty, and mentioned some problems with it, so needs work, he actually mentioned that as it got hotter the problem would get worse. Which is what was happening, so hopefully this is the issue. Should get it back next week. Costing me £90

 

Might not have needed a new battery but don't mind having one anyway.

[Jim Bowen 1]

Yeah that's got 520 CCA so that should be fine Jim.

 

Si

 

Got the battery and comparing it to the one in car. Original = 60ah and 540cca, new one = 52ah and 520cca. New one is also quite a bit smaller in size.

 

Does the higher ah make much difference?

[robrado974 1]

Let’s hope the problem will be sorted then Jim . My neighbors must think I’m nuts . The bonnet is always up , with me tinkering. It’s taken me three weeks to sort the coolant leaks .Then I go for a drive . Then the bonnet is up again with parts all over the place again lol .

[1xshaunx1 27]

I’ve just bought a Bosch, £85 that is 60ah same as one in car. I’d see if I could exchange it for another one Jim on a cold morning that one morning might struggle after a while.

[vw rule 19]

I think the (AH) stands for amp's per hour or something like that, and (CCA) is cold cranking amp's, as long as you get a replacement battery the same AH rating or slightly lower is fine or - by 5 to 8 AH is still acceptable but I wouldn't go any higher than original spec as the alternator will be working over time, possibly as the battery won't reach full charge as quickly as it would if it had original AH spec or slightly lower.

I would only go to a higher AH spec if you've got a massive stereo amp or other added electronics that draw more amp's so to speak.

 

Si

[Bauhaus 3]

65AH in my opinion should be the minimum size for any Corrado, to go any bigger depends on what your alternator is rated at.

The CCA rating is the peak amps the battery will deliver in short bursts ,and a lower AH battery rating will limit how many times you can crank the engine until the battery goes “flat” before starting, so if your car is an easy starter the battery you have will be ok.

[Jim Bowen 1]

I put the original battery on the charger and it tests it and charges it up, all went ok. Charged up to 12.4-12.5v, left it on the side for 3 days and it now reads 12.1v (not been connected up to anything)

 

Is that a sign the battery is a bit duff? Can't get hold of the people that sent me to new battery to return it, but for the amount it'll cost to post i may as well sell it to someone for £15 less than i bought it.

 

The people that did my alternator seemed to know a lot about batteries and might get one from them, Says you can fit an AGM battery instead of a flooded one to a non-start-stop car with no issues, but not vice-versa

[Dox 22]

I put the original battery on the charger and it tests it and charges it up, all went ok. Charged up to 12.4-12.5v, left it on the side for 3 days and it now reads 12.1v (not been connected up to anything)

 

Is that a sign the battery is a bit duff? Can't get hold of the people that sent me to new battery to return it, but for the amount it'll cost to post i may as well sell it to someone for £15 less than i bought it.

 

The people that did my alternator seemed to know a lot about batteries and might get one from them, Says you can fit an AGM battery instead of a flooded one to a non-start-stop car with no issues, but not vice-versa

 

Each cell in a battery is 2.1V, times 6 is 12.6V, you don't really want to see anything less than 12.6V, but you don't know the accuracy of the meter you're using?

 

If a battery is capable of cranking a cold engine to a position when its running, its easily capable of maintaining it until its charge is depleted.

 

If you charge a battery from either a 240V charger or the cars alternator you need to allow the battery to rest for a few hours for the voltage readings to be meaningful.

[Jim Bowen 1]

Kept the old battery on for now as think it might be ok. Got the new alternator fitted and car is still misfiring.

 

Didn't even need to warm up this time was doing it straight away.

 

Swapped the maf for a spare i had and it made no difference.

 

Wonsering whether to try some redex through it, maybe an injector a bit blocked?

[robrado974 1]

Is the car pulling well with no loss of power jim , apart from the miss fire its fine ?.

[Jim Bowen 1]

Nah, won't accelerator properly, really lumpy like not all cylinders are running. Pops and bangs too. Massive loss of power

[robrado974 1]

Is it possible to post a vid of it sat at idle Jim ?.

[robrado974 1]

As well as a hunting idle , I have experienced a loss of power / throttle?, last week . I went out in the car today to get some bits . After putting £20.00 of fuel in , just to make sure the gauge wasn’t playing up , I put my foot down and it struggled a bit . It was fine for the rest of the journey, putting my foot down produced no problems. I saw a vid on YouTube tonight, where the bloke was removing each lead in turn from the coil pack (in my case dizzy), he found the miss fire as one lead did not effect the engine .

[Jim Bowen 1]

Tried to get a video, but typical corrado, it did it for a few seconds and then cleared up. Too wet to take car out, so we'll look another day.

 

Did a vagcom again and it said maf short to ground- intermittent. Not sure if this is because i changed the maf yesterday or its a wiring issue.

 

Half tempted to just get stripping it down now ready for the new engine and obd2 swap, and then see if i have the same issue.

 

Might look at changing fuel pump at same time as that is still the 233,000mile original.

 

Starting to wonder if it is too

do with fuel as started happening shortly after filling up. Although it seems more like an electrical ignition problem as unburnt fuel is going through the exhaust imo

[robrado974 1]

It’s a pita isn’t it Jim . I just pulled each plug from the dizzy separately and could not hear a change . If you take a cylinder away you must notice. I’m going to put something in to hold the throttle open above idle , I think because the idle is rough it’s hard to hear , but if it’s running around 2k I should be able to tell .

[Dox 22]

Be careful what you open the throttle with, if it gets sucked on you may end up with a beggar headache

[robrado974 1]

Hi Dox , I was only going to put a lolly sick or something under the lip where you would normally operate it with your finger to increase the revs . I wouldn’t jam the butterfly open with anything.

[Jim Bowen 1]

That's what I've done in the past Rob.

[fla 9]

Rob you could use a slightly heavy piece of wood or brick on the accelerator. Pulling a lead shoukd definitely affect the engine note. Could you remove the sparks and post up some pics? Might shine some light on the issue.

[robrado974 1]

I would put it on my own thread on the subject hasan , but it’s difficult to post pics at the moment. I dont want to clog up Jim’s page either. But I will be pulling them to take a look .

[Dox 22]

Tried to get a video, but typical corrado, it did it for a few seconds and then cleared up. Too wet to take car out, so we'll look another day.

 

Did a vagcom again and it said maf short to ground- intermittent. Not sure if this is because i changed the maf yesterday or its a wiring issue.

 

Half tempted to just get stripping it down now ready for the new engine and obd2 swap, and then see if i have the same issue.

 

Might look at changing fuel pump at same time as that is still the 233,000mile original.

 

Starting to wonder if it is too

do with fuel as started happening shortly after filling up. Although it seems more like an electrical ignition problem as unburnt fuel is going through the exhaust imo

 

The rubber mounts inside my swirl pot rotted away and allowed the pump to move around draining the swirl pot causing a miss around roundabouts on low tank levels. Mine was a beige coloured pot with internal mounts, not the more common white with external mounts.

 

If you're unplugging stuff with the engine running you will cause fault codes doing so, its best to record them, clear them then drive again without fiddling with any sensors before a rescan to give a better insight.

[Dox 22]

Hi Dox , I was only going to put a lolly sick or something under the lip where you would normally operate it with your finger to increase the revs . I wouldn’t jam the butterfly open with anything.

 

My bad, its funny the conclusions I can jump to when I read stuff and then post too quickly lol